“Leo was holding hands with Toni, clearly he was proud she was his girlfriend and was showing her off.”

The pair—who were joined by Leo’s longtime friend Lukas Haas—sat in the Moët and Chandon suite, where they split their time between the indoor and outdoor areas while watching fan favorites Serena Williams and Andy Murray.

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Between sips of champagne in the suite, another bystander observed tennis fanatic Leo getting another treat—visits from tennis legends!

“Leo moved indoors and was seen inside the suite sneaking kisses with girlfriend Toni, before the legendary actor got a surprise visit from an unexpected fan, professional tennis player Novak Djokovic, who specially came up to the suite to meet him,” the onlooker shared.

The onlooker told In Touch that after Leo appeared on the balcony, fans spotted him and approached him for pictures after the Titanic theme song, “My Heart Will Go On,” was played over the loud speaker.

Based on their behavior, it’s safe to say Leo’s heart is only going on for Toni!

Leo and the 21-year-old model have reportedly been together since May.